The present invention relates to apparatus for moving discrete paper sheets or analogous commodities, and more particularly to improvements in apparatus which can move successive sheets along a first path and include means for diverting selected sheets from the first path into a second path.
The need for diverting certain sheets of a succession of rapidly advancing discrete sheets from a first path into a second path arises in many types of paper processing and like machines, e.g., to ssegregate unsatisfactory sheets from acceptable sheets, to break up a continuous stream of discrete sheets into two or more streams, or to divert sheets to an inspecting station at regular or randomly selected intervals.
In presently known sheet moving apparatus, the means for diverting selected sheets from a portion of a first path into a second path includes mechanical deflecting or diverting devices. For example, it is known to employ mechanical switching devices similar to railroad switches which can be pivoted or otherwise moved into the path of an oncoming sheet to divert the oncoming sheet (or the oncoming sheet and one or more next-following sheets) into a second path. Certain other types of presently known diverting devices resemble or constitute rollers or drums having portions of larger and smaller radius. The portion or portions of smaller radius permit successive sheets to advance along a first path, and the portion or portions of larger radius divert the oncoming sheet or sheets into a second path.
A drawback of mechanical diverting devices is that they cannot be employed when the sheets are transported at a high or extremely high speed because a mechanical part which is introduced into the path of an oncoming rapidly advancing sheet is likely to deface and/or otherwise damage the leader of the oncoming sheet. Moreover, the inertia of mechanical diverting devices is relatively high so that they cannot be introduced between a preceding sheet and an oncoming sheet when the sheets are transported at an elevated speed, especially if the width of clearances or gaps between neighboring sheets is negligible.